From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jack Stone <jwjstone@fastmail.fm>
Subject: Re: [PATCH] fs/eventpoll.c: fix compilation warning
Date: Fri, 14 Jan 2011 10:55:14 +0000
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To: viresh kumar <viresh.kumar@st.com>
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On 14/01/2011 09:38, viresh kumar wrote:
> On 01/14/2011 03:03 PM, Jack Stone wrote:
>>>> -	long slack;
>>>> +	long slack = 0;
>>>> 	wait_queue_t wait;
>>>> 	struct timespec end_time;
>>>> 	ktime_t expires, *to = NULL;
>> I don't think this is the correct fix. This function is fine unless timeout is negative.
>>
>> If a negative timeout is possible then this function will create timer far in the future.
>> I'll leave it up to the maintainer how to solve that one. The two solutions I can see are making
>> timeout unsigned or extending the bottom case of the if to <=0.
>>
>> Either way we should use uninitalized_var() rather than setting it to zero.
> 
> Using uninitialized var gives compilation warning, How should we fix that.
> 

I meant something like
-  long slack;
+  long uninitialized_var(slack);

I just had a go at generating this warning and couldn't. I've tried GCC
4.4.5 (From Fedora 13) and latest sparse.

Thanks,

Jack